The invention concerns a bathtub lift with a lifting plate upwardly and downwardly guided on a support frame and actuated by a hydraulic lifting device, and a valve device featuring an inlet valve and an outlet valve whose valve plungers are actuatable as required by a hand-operated rocker, whereby the two valve plungers are of identical design, displaceably guided with parallel axes in a valve housing and preloaded in their closed position with inbuilt springs, and a connection leading to the lifting device is connected to an outlet opening when the outlet valve is open.
U.S. Pat. No. 3,280,409 shows such a bathtub lift. The valve device is positioned at the side and at a distance from the support frame and from the lifting plate. If the former is raised to its limit of travel, its upward motion is limited by an adjustable stop. The pressure in the hydraulic lifting device increases up to the supply pressure in the pressurized water line. The hydraulic lifting device is subjected to high load in the process.
EP Patent 00 74 460 shows a bathtub lift on which the lifting device consists of a flexible hose. If such hoses are subjected frequently and for extended periods to the full pressure of the water supply line, there is a risk of leakage.
U.S. Pat. No. 4,624,019 shows a lifting appliance with a metal lifting cylinder. A three-way valve positioned at a distance from the lifting plate is actuated by a hand-operated pivoted lever acting upon a Bowden cable. At its limit of travel, another Bowden cable draws an actuating rocker of the three-way valve towards another actuation position so that the lifting cylinder is disconnected from the pressurized water supply; the discharge valve, however, is opened as a result and the lifting plate descends.